src/Pure/Thy/thy_info.ML
changeset 6211 43d0efafa025
parent 5211 c02b0c727780
child 6219 b360065c2b07
--- a/src/Pure/Thy/thy_info.ML	Wed Feb 03 17:29:12 1999 +0100
+++ b/src/Pure/Thy/thy_info.ML	Wed Feb 03 17:29:48 1999 +0100
@@ -1,132 +1,350 @@
 (*  Title:      Pure/Thy/thy_info.ML
     ID:         $Id$
-    Author:     Stefan Berghofer and Markus Wenzel, TU Muenchen
-
-Theory loader database.
-*)
+    Author:     Markus Wenzel, TU Muenchen
 
-type thy_info =
-  {path: string,
-    children: string list, parents: string list,
-    thy_time: string option, ml_time: string option,
-    theory: theory option};
+Theory loader database: theory and file dependencies, theory values
+and user data.
 
-(*
-  path: directory where theory's files are located
-	(* FIXME do not store absolute path!!! *)
-
-  thy_time, ml_time = None     theory file has not been read yet
-                    = Some ""  theory was read but has either been marked
-                               as outdated or there is no such file for
-                               this theory (see e.g. 'virtual' theories
-                               like Pure or theories without a ML file)
-  theory = None  theory has not been read yet
-
-  parents: While 'children' contains all theories the theory depends
-           on (i.e. also ones quoted in the .thy file),
-           'parents' only contains the theories which were used to form
-           the base of this theory.
+TODO:
+  - check_thy: include ML stamp (!?!?);
+  - check all these versions of 'use' (!!);
+  - errors during require etc.: include initiators (!?);
+  - data: ThyInfoFun;
+  - remove operation (GC!?);
+  - update_all operation (!?);
+  - put_theory:
+      . include data;
+      . allow for undef entry only;
+      . elim (via theory_ref);
+  - stronger handling of missing files (!?!?);
+  - register_theory: do not require finished parents (!?) (no?);
+  - observe verbose flag;
 *)
 
 signature BASIC_THY_INFO =
 sig
   val theory: string -> theory
-end
+  val theory_of_sign: Sign.sg -> theory
+  val theory_of_thm: thm -> theory
+  val touch_thy: string -> unit
+  val use_thy: string -> unit
+  val update_thy: string -> unit
+  val time_use_thy: string -> unit
+end;
 
 signature THY_INFO =
 sig
   include BASIC_THY_INFO
-  val mk_info: string * string list * string list * theory -> string * thy_info
-  val loaded_thys: thy_info Symtab.table ref
-  val get_thyinfo: string -> thy_info option
-  val store_theory: theory -> unit
-  val path_of: string -> string
-  val children_of: string -> string list
-  val parents_of_name: string -> string list
-  val thyinfo_of_sign: Sign.sg -> string * thy_info
-  val theory_of_sign: Sign.sg -> theory
-  val theory_of_thm: thm -> theory
+  val verbose: bool ref
+  val names: unit -> string list
+  val get_theory: string -> theory
+  val put_theory: theory -> unit
+  val load_file: Path.T -> unit
+  val use_thy_only: string -> unit
+  val begin_theory: string -> string list -> theory
+  val end_theory: theory -> theory
+  val finish_all: unit -> unit
+  val register_theory: theory -> unit
 end;
 
-
-structure ThyInfo: THY_INFO =
-struct
-
-(* loaded theories *)
-
-fun mk_info (name, children, parents, theory) =
-  (name, {path = "", children = children, parents = parents,
-    thy_time = Some "", ml_time = Some "", theory = Some theory}: thy_info);
-
-(*preloaded theories*)
-val loaded_thys = ref (Symtab.empty: thy_info Symtab.table);
-
+signature PRIVATE_THY_INFO =
+sig
+  include THY_INFO
+(* FIXME
+  val init_data: Object.kind -> (Object.T * (Object.T -> Object.T) *
+    (Object.T * Object.T -> Object.T) * (Sign.sg -> Object.T -> unit)) -> unit
+  val print_data: Object.kind -> string -> unit
+  val get_data: Object.kind -> (Object.T -> 'a) -> string -> 'a
+  val put_data: Object.kind -> ('a -> Object.T) -> 'a -> unit
+*)
+end;
 
-(* retrieve info *)
-
-fun err_not_stored name =
-  error ("Theory " ^ quote name ^ " not stored by loader");
-
-fun get_thyinfo name = Symtab.lookup (! loaded_thys, name);
-
-fun the_thyinfo name =
-  (case get_thyinfo name of
-    Some info => info
-  | None => err_not_stored name);
-
-fun thyinfo_of_sign sg =
-  let val name = Sign.name_of sg
-  in (name, the_thyinfo name) end;
+structure ThyInfo: PRIVATE_THY_INFO =
+struct
 
 
-(*path where theory's files are located*)
-val path_of = #path o the_thyinfo;
+(** thy database **)
+
+(* messages *)
+
+val verbose = ref false;
+
+fun gen_msg txt [] = txt
+  | gen_msg txt names = txt ^ " " ^ commas_quote names;
+
+fun loader_msg txt names = gen_msg ("Theory loader: " ^ txt) names;
+
+val show_path = space_implode " via " o map quote;
+fun cycle_msg name names = loader_msg ("cyclic dependency of " ^ show_path (name :: names)) [];
 
 
-(*try to get the theory object corresponding to a given signature*)
-fun theory_of_sign sg =
-  (case thyinfo_of_sign sg of
-    (_, {theory = Some thy, ...}) => thy
-  | _ => sys_error "theory_of_sign");
+(* derived graph operations *)		(* FIXME more abstract (!?) *)
 
-(*try to get the theory object corresponding to a given theorem*)
-val theory_of_thm = theory_of_sign o #sign o rep_thm;
+fun add_deps name parents G =
+  foldl (fn (H, parent) => Graph.add_edge_acyclic (parent, name) H) (G, parents)
+    handle Graph.CYCLES namess => error (cat_lines (map (cycle_msg name) namess));
 
-(*get all direct descendants of a theory*)
-fun children_of t =
-  (case get_thyinfo t of
-    Some {children, ...} => children
-  | None => []);
+fun del_deps name G =           (* FIXME GC (!?!?) *)
+  foldl (fn (H, parent) => Graph.del_edge (parent, name) H) (G, Graph.imm_preds G name);
 
-(*get all direct ancestors of a theory*)
-fun parents_of_name t =
-  (case get_thyinfo t of
-    Some {parents, ...} => parents
-  | None => []);
-
-(*get theory object for a loaded theory*)
-fun theory name =
-  (case get_thyinfo name of
-    Some {theory = Some t, ...} => t
-  | _ => err_not_stored name);
+fun update_node name parents entry G =
+  add_deps name parents
+    (if can (Graph.get_node G) name then del_deps name G else Graph.new_node (name, entry) G);
 
 
-(* store_theory *)
+(* thy database *)
+
+type deps =
+  {present: bool, outdated: bool,
+    master: File.info option, files: (Path.T * File.info option) list} option;
+
+fun make_depends present outdated master files =
+  Some {present = present, outdated = outdated, master = master, files = files}: deps;
 
-fun store_theory thy =
-  let
-    val name = PureThy.get_name thy;
-    val {path, children, parents, thy_time, ml_time, theory = _} =
-      the_thyinfo name;
-    val info = {path = path, children = children, parents = parents,
-      thy_time = thy_time, ml_time = ml_time, theory = Some thy};
-  in
-    loaded_thys := Symtab.update ((name, info), ! loaded_thys)
-  end;
+type thy = deps * (theory * Object.T Symtab.table) option;
+type kind = Object.kind * (Object.T * (Object.T -> unit));
+
 
+local
+  val database = ref (Graph.empty: thy Graph.T, Symtab.empty: kind Symtab.table);
+in
+
+fun get_thys () = #1 (! database);
+fun get_kinds () = #2 (! database);
+fun change_thys f = database := (f (get_thys ()), get_kinds ());
+fun change_kinds f = database := (get_thys (), f (get_kinds ()));
 
 end;
 
 
+(* access thy graph *)
+
+fun thy_graph f x = f (get_thys ()) x;
+fun get_names () = map #1 (Graph.get_nodes (get_thys ()));
+
+
+(* access thy *)
+
+fun lookup_thy name = Some (thy_graph Graph.get_node name) handle Graph.UNDEFINED _ => None;
+
+fun get_thy name =
+  (case lookup_thy name of
+    Some thy => thy
+  | None => error (loader_msg "nothing known about theory" [name]));
+
+fun change_thy name f = (get_thy name; change_thys (Graph.map_node name f));
+
+
+(* access deps *)
+
+val lookup_deps = apsome #1 o lookup_thy;
+val get_deps = #1 o get_thy;
+fun change_deps name f = change_thy name (fn (deps, x) => (f deps, x));
+
+fun get_files name = (case get_deps name of Some {files, ...} => files | _ => []);
+fun is_finished name = is_none (get_deps name);
+
+
+(* access theory *)
+
+fun get_theory name =
+  (case get_thy name of
+    (_, Some (theory, _)) => theory
+  | _ => error (loader_msg "undefined theory entry for" [name]));
+
+val theory_of_sign = get_theory o Sign.name_of;
+val theory_of_thm = theory_of_sign o Thm.sign_of_thm;
+
+fun put_theory theory =
+  change_thy (PureThy.get_name theory) (fn (deps, _) => (deps, (Some (theory, Symtab.empty))));
+
+
+
+(** thy data **)  (* FIXME *)
+
+
+
+(** thy operations **)
+
+fun FIXME msg = writeln ("DEBUG:\n" ^ msg);
+
+
+(* touch_thy -- mark as outdated *)
+
+fun touch_thy name = change_deps name
+  (fn None => (warning (loader_msg "tried to touch finished theory" [name]); None)
+    | Some {present, outdated = _, master, files} =>
+        make_depends present true master files);
+
+
+(* load_thy *)
+
+fun required_by [] = ""
+  | required_by initiators = " (required by " ^ show_path (rev initiators) ^ ")";
+
+fun load_thy ml time initiators name parents =
+  let
+    val _ = if name mem_string initiators then error (cycle_msg name (rev initiators)) else ();
+    val _ = writeln ("Loading theory " ^ quote name ^ required_by initiators);
+
+    val _ = seq touch_thy (thy_graph Graph.all_succs [name]);
+    val master = ThyLoad.load_thy name ml time;
+
+    val files = get_files name;
+    val missing_files = mapfilter (fn (path, None) => Some (Path.pack path) | _ => None) files;
+  in
+    if null missing_files then ()
+    else warning (loader_msg ("unresolved dependencies on file(s) " ^ commas_quote missing_files ^
+      "\nfor theory") [name]);
+    change_deps name (fn _ => make_depends true false (Some master) files)
+  end;
+
+
+(* load_file *)
+
+fun load_file path =
+  let
+    fun provide name info (deps as Some {present, outdated, master, files}) =
+          if exists (equal path o #1) files then
+            make_depends present outdated master (overwrite (files, (path, Some info)))
+          else (warning (loader_msg ("undeclared dependency on file " ^ quote (Path.pack path) ^
+            "\nfor theory") [name]); deps)
+      | provide _ _ None = None;
+  in
+    (case apsome PureThy.get_name (Context.get_context ()) of
+      None => (ThyLoad.load_file path; ())
+    | Some name =>
+        if is_some (lookup_thy name) then change_deps name (provide name (ThyLoad.load_file path))
+        else (ThyLoad.load_file path; ()))
+  end;
+
+
+(* require_thy *)
+
+fun init_deps master files = make_depends false false master (map (rpair None) files);
+
+fun load_deps name ml =
+  let val (master, (parents, files)) = ThyLoad.deps_thy name ml
+  in (Some (init_deps (Some master) files), parents) end;
+
+fun file_current (_, None) = false
+  | file_current (path, info) = info = ThyLoad.check_file path;
+
+fun current_deps ml strict name =
+  (case lookup_deps name of
+    None => (false, load_deps name ml)
+  | Some deps =>
+      let val same_deps = (None, thy_graph Graph.imm_preds name) in
+        (case deps of
+          None => (true, same_deps)
+        | Some {present, outdated, master, files} =>
+            if present andalso not strict then (true, same_deps)
+            else
+              let val master' = Some (ThyLoad.check_thy name) in
+                if master <> master' then (false, load_deps name ml)
+                else (not outdated andalso forall file_current files, same_deps)
+              end)
+      end);
+
+fun outdated name =
+  (case lookup_deps name of Some (Some {outdated, ...}) => outdated | _ => false);
+
+fun require_thy ml time strict keep_strict initiators name =
+  let
+    val require_parent =
+      require_thy ml time (strict andalso keep_strict) keep_strict (name :: initiators);
+    val (current, (new_deps, parents)) = current_deps ml strict name handle ERROR =>
+      error (loader_msg "The error(s) above occurred while examining theory" [name] ^ "\n" ^
+        required_by initiators);
+    val pre_outdated = outdated name;
+  in
+    seq require_parent parents;
+    if current andalso pre_outdated = outdated name then ()	(* FIXME ?? *)
+    else
+      ((case new_deps of
+        Some deps => change_thys (update_node name parents (deps, None))
+      | None => ()); load_thy ml time initiators name parents)
+  end;
+
+val weak_use_thy = require_thy true false false false [];
+val use_thy      = require_thy true false true false [];
+val update_thy   = require_thy true false true true [];
+val time_use_thy = require_thy true true true false [];
+val use_thy_only = require_thy false false true false [];
+
+
+(* begin / end theory *)		(* FIXME tune *)
+
+fun begin_theory name parents =
+  let
+    val _ = seq weak_use_thy parents;
+    val theory = PureThy.begin_theory name (map get_theory parents);
+    val _ = change_thys (update_node name parents (init_deps None [], Some (theory, Symtab.empty)));
+  in theory end;
+
+fun end_theory theory =
+  let val theory' = PureThy.end_theory theory
+  in put_theory theory'; theory' end;
+
+
+(* finish entries *)
+
+(* FIXME
+fun finishs names =
+  let
+    fun err txt bads =
+      error (loader_msg txt bads ^ "\n" ^ gen_msg "cannot mark" names ^ " as finished");
+
+    val all_preds = thy_graph Graph.all_preds names;
+    val noncurrent = filter_out is_current all_preds;
+    val unfinished = filter_out is_finished (all_preds \\ names);
+  in
+    if not (null noncurrent) then err "non-current theories" noncurrent
+    else if not (null unfinished) then err "unfinished ancestor theories" unfinished
+    else seq (fn name => change_thy name (apfst (K Finished)))
+  end;
+
+fun finish name = finishs [name];
+*)
+
+fun update_all () = ();         (* FIXME fake *)
+
+fun finish_all () = (update_all (); change_thys (Graph.map_nodes (fn (_, entry) => (None, entry))));
+
+
+(* register existing theories *)
+
+fun register_theory theory =
+  let
+    val name = PureThy.get_name theory;
+    val parents = Theory.parents_of theory;
+    val parent_names = map PureThy.get_name parents;
+
+    fun err txt bads =
+      error (loader_msg txt bads ^ "\n" ^ gen_msg "cannot register theory" [name]);
+
+    val unfinished = filter_out is_finished parent_names;
+    fun get_variant (x, y_name) =
+      if Theory.eq_thy (x, get_theory y_name) then None
+      else Some y_name;
+    val variants = mapfilter get_variant (parents ~~ parent_names);
+
+    fun register G =
+      (Graph.new_node (name, (None, Some (theory, Symtab.empty))) G
+        handle Graph.DUPLICATE _ => err "duplicate theory entry" [])
+      |> add_deps name parent_names;
+  in
+    if not (null unfinished) then err "unfinished parent theories" unfinished
+    else if not (null variants) then err "different versions of parent theories" variants
+    else change_thys register
+  end;
+
+
+(*final declarations of this structure*)
+val theory = get_theory;
+val names = get_names;
+
+end;
+
 structure BasicThyInfo: BASIC_THY_INFO = ThyInfo;
 open BasicThyInfo;